JPH0570346U - Lumber support mechanism - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a lumbar support mechanism having a simple structure, excellent operability and lightweight, and having a wide adjustment range of the support range. [Structure] A support plate 4 in contact with the backrest surface is attached to the lower end of a leaf spring 2a whose upper end is supported by a backrest frame 1 of a seatback 20, and
A rotatable eccentric cam 6 is provided on the rear surface of the upper portion of the leaf spring 2a, and the lower end of the leaf spring 2a is moved forward and backward by the rotation of the eccentric cam 6 to adjust the front-back position of the support plate 4. The leaf springs 2a and 2b having different lengths are used as front and rear leaf springs 2a and 2b. Similar to the above, the position of the support plate 4 is adjusted.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a lumbar support mechanism having a simple structure, excellent operability and light weight, and having a wide adjustment range of a support range.

[0002]

[Prior Art]

 For example, in recent automobile seats and the like, various ones in which a lumbar support mechanism is incorporated in the backrest portion of the seat have been developed for the purpose of improving seating comfort performance, and JP-A-63-150553 and JP-A-62-15252 have been developed. Many have been proposed as Japanese Patent Publication No. 62-66538.

However, the conventional one has a problem that the structure is complicated and the operation is complicated because the support plate is adjusted by a gear mechanism, a notch lock mechanism, a link mechanism, or the like, and the support range is also increased. There was also a problem that the adjustment range was small and it was not possible to make satisfactory adjustments. Further, there is a problem that the weight is heavy and cannot be reduced, and the number of parts is large, so that it takes a long time for assembling work.

[0004]

[Problems to be solved by the device]

 The present invention solves the above-mentioned conventional problems, has a simple structure and is excellent in operability, and has a wide adjustment range of the support range, so that the seat can be fitted to any body shape or driving posture. It was completed for the purpose of providing a lumbar support mechanism that can be attached, and has a large number of parts, which can greatly reduce weight, facilitate assembly work, and reduce manufacturing costs. .

[0005]

[Means for Solving the Problems]

 The present invention, which has been made to solve the above-mentioned problems, has a leaf spring mounted on the backrest frame of a seatback with its upper end portion mounted with a support plate at the lower end portion of the leaf spring. An eccentric cam that is rotated by an external operation is arranged on the rear surface of the upper portion of the leaf spring, and a support plate is adjustable back and forth by the rotation of the eccentric cam. According to the first invention, front and rear leaf springs having different lengths are attached to the backrest frame of the seat back with their upper ends, and a support plate is attached to the lower ends of the leaf springs. An eccentric cam that is rotated by an external operation is arranged between the upper parts of the support plate and the support plate can be adjusted back and forth by the rotation of the eccentric cam. The lumbar support mechanism, characterized by that it is an second invention.

[0006]

[Action]

 With this type of structure, the user can adjust the front and rear position of the support plate by external operation and use it while it is installed in the seat back. However, the front-rear position adjustment of the support plate can be performed extremely easily because the eccentric cam arranged on the back surface of the upper portion of the leaf spring can be rotated by an external operation.

[0007]

【Example】

 The present invention will now be described in detail with reference to the illustrated embodiment. The drawing shows a state in which it is incorporated into a vehicle seat back 20. In the figure, 1 is a backrest frame, and 2a and 2b are elastic attached to the backrest frame 1 via a bracket 3. Two long and short leaf springs, 4 are front and rear leaf springs, and 2 is a support plate attached to the tip of both leaf springs 2a and 2b. The two long and short leaf springs 2a and 2b shown in the embodiment are substantially constant in the front and rear. It is a substantially V-shaped member that is bent and formed with a width gap maintained, and is attached to and suspended from the backrest frame 1 with a bent portion at the upper end. Further, a spring receiving frame 5 for contacting a leaf spring 2b on the rear side and restricting the movement to the rear side is provided laterally on the lower portion of the backrest frame 1. The leaf springs 2a and 2b may be formed of a single elastic material as shown in the figure, or may be formed of a single elastic material cut at the bracket 3. Only one of the front leaf springs 2a may be provided, and the material, shape, gap length and the like may be arbitrary according to the seat shape and the like.

A rotatable eccentric cam 6 is provided between the upper portions of the two leaf springs 2a and 2b so as to contact the rear surface of the upper portion of the front leaf spring 2a. The eccentric cam 6 is attached to a shaft 8 supported by bearing plates 7 on both sides of the backrest frame 1, and the rotation knob 9 provided at one end of the shaft 8 and the switch operation are performed. The leaf springs 2a and 2b can be freely rotated by an external operation.

In the case of the above-mentioned structure, the user is able to adjust the front-back position of the support plate 4 by an external operation in the state of being incorporated in the seatback 20 and use the same. Similar to this type of lumbar support mechanism, the front-back position adjustment of the support plate 4 is performed by adjusting the eccentric cam 6 provided between the front leaf springs 2a and 2b in the upper portion of the front leaf spring 2a. This can be done extremely easily by turning. That is, when the rotation knob 9 on the side surface of the seat is rotated to rotate the eccentric cam 6, the gap between the leaf springs 2a and 2b changes according to the eccentric amount of the eccentric cam 6. In this case, As shown in FIG. 2, since the spring receiving frame 5 is in contact with the leaf spring 2b on the rear side and the movement to the rear side is restricted, when the eccentric amount of the eccentric cam 6 becomes large, the leaf springs 2a, 2b. The gap between the two is widened toward the front, and along with this, the support plate 4 attached to the tip of the leaf springs 2a, 2b moves forward to support the backrest surface of the seatback 20 more strongly than the inside. Becomes

To weaken the support of the support plate 4, the eccentric cam 6 may be operated so as to narrow the gap between the leaf springs 2a and 2b. The degree can be set arbitrarily, and by increasing the displacement amount of the eccentric cam 6, the range of the adjustment width can be freely selected. Further, in the above-mentioned embodiment, the one in which the support plate 4 is composed of one sheet has been described. However, as shown in FIG. 4, the leaf springs 2a and 2b are respectively independent at the tip portions thereof. Support plates 4 and 4 can be attached, and in this case, finer adjustment can be realized from the front, rear, top and bottom.

Further, since the lumbar support mechanism according to the present invention has an extremely simple structure and a small size, it can be similarly incorporated into the headrest portion 21 as shown in FIG. It is possible to maintain a more comfortable driving posture by adjusting the supportability to an arbitrary level.

[0012]

[Effect of the device]

 As is clear from the above description, the present invention has a simple structure and is excellent in operability, and the adjustment range of the support range is large, so that the seat can be attached to any body shape and driving posture. In addition, the number of parts is small, the weight is significantly reduced, the assembly work is facilitated, and the manufacturing cost is reduced. Therefore, the present invention has an extremely large practical value as a lumbar support mechanism that eliminates the conventional problems.

[Brief description of drawings]

FIG. 1 is an overall perspective view showing an embodiment of the present invention.

FIG. 2 is a side view showing an essential part of an embodiment of the present invention.

FIG. 3 is a rear view showing an essential part of the embodiment of the present invention.

FIG. 4 is a perspective view of a main part showing another embodiment.

FIG. 5 is a side view showing another embodiment.

[Explanation of symbols]

 1 Backrest frame 2a Leaf spring 2b Leaf spring 4 Support plate 6 Eccentric cam 20 Seat back

Claims (4)

[Scope of utility model registration request] 1. A backrest frame of a seat back (20)
Attach the leaf spring (2a) to the (1) with its upper end and attach the support plate (4) to the lower end of the leaf spring (2a). An eccentric cam (6) that is rotated by an external operation is arranged, and the eccentric cam (6) is rotated to provide a support plate.
A lumbar support mechanism characterized in that (4) is adjustable back and forth. 2. The backrest frame of the seat back (20)
Front and rear leaf springs (2a), (2b) with different lengths in (1)
Install the leaf spring (2
Attach the support plate (4) to the lower ends of a) and (2b),
Further, an eccentric cam (6) which is rotated by an external operation is arranged between the upper portions of the leaf springs (2a) and (2b), and the support plate (4) is rotated by the rotation of the eccentric cam (6). The lumbar support mechanism is characterized by being adjustable back and forth. 3. The front leaf spring (2a) and the rear leaf spring (2b) are formed in series.
Lumbar support mechanism described in. 4. The lumbar support mechanism according to claim 2, wherein separate support plates (4) are attached to the lower end portions of the front and rear leaf springs (2a), (2b), respectively.